This problem may occur on Summit Utilitrucks and Payloaders Models equipped with the AC Drive system.
If you have the motor temp fault, go to the vehicle status screen (If equipped) to check the motor temp. Let the vehicle sit for two hours to allow cooling. Come back and check the temp. If it is still at 390. The temp. sensor has failed and the motor will have to be replaced.
This can be cause by:
Bad temp sensor / replace.
It has lost connection due to a broken wire / check all connections.
Corrosion / look for corrosion and clean connections.
Plug pulled apart / reconnect plug
The harness can also get tied up so tight it eventually pulls the plug apart / cut zip tie to add slack in the harness and re-zip tie.